Updates jquery-rails gem.
Refactors the loading of external libraries and Alchemy mixins.

Basically we don't require everything at boot time anymore.
Only the global stuff, like other engines is loaded at boot time.
All other stuff gets required where its needed.

This gives several advantages:

* Faster boot up time. Especially while running single tests.
* Possibility to introduce a reduced faster spec helper.
* Clearer view on dependencies of classes. Especially in models.
Introduces a fast_specs helper.

This reduced faster spec helper, runs your specs without any extra stuff.

Just require 'fast_specs' in your specs instead of 'spec_helper'.
JSONify options params while passing them around between ruby and javascript.

This fixes some weird url parsing bugs in jQuery and finally drops the requirement for `HashWithIndifferentAccess` in `EssencePicture#edit` view.